// ComponentA.vue
<template>
  <div>
    <button @click="sendMessage">Send Message</button>
  </div>
</template>

<script>
import { useEventBus } from './EventBus.js';

export default {
  methods: {
    sendMessage() {
      const eventBus = useEventBus();
      eventBus.emit('message', 'Hello from Component A');
    }
  }
};
</script>